Piston engine



s SheetsSheet 1.

L. SHAW. PI ENGINE.

(No Model.)

No. 442,401. Patented Dec. 9, 1890.

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(No Model.) 3' Sheets-Sheet 2.

L. M. SHAW, PISTON ENGINE.

No. 442,401. Patented Dec. 9, 1890.

(No Model.)

L. M. SHAW. PISTON ENGINE.

No. 442,401. 7 Patented Dec. 9, 1890.

3 Sheets-Sheet 3.

Nrrnn terns PATENT OFFICE.

LEVI M. Sill UV, OF GYPSUM, KANSAS, ASSIGNOR TO HENRY C. STAVER, OFCHICAGO, ILLINOIS.

PISTON ENGINE.

SPEC'EFICATION forming part of Letters Patent No. 442,401, datedDecember 9, 1890.

Application filed December 4, 1839. Serial No. 382,587. (No model.)

To aZZ whom it may concern.-

Be it known that I, LEVI M. SHAW, of Gypsum, in the county of Saline andState of Kansas, have in "ented certain new and useful Improveinents inPiston Engines; and Ido hereby declare that the following is a full,clear, and exact description of the invention, which will enable othersskilled in the art to which it pertains to make and use the same, referto ence being had to the accompanying drawings, forming a part hereof,in which 7 Figure 1 is a central longitudinal section with thepiston-shaft and the driven shaft in elevation. Fig. 2 is across-section through the center of the steam-chest with the piston andabutment in elevation. Fig. is a sectional elevation of the steam-chestwith the flange of the piston partly broken away to show the abutment,looking down thereon.

Fig. 4 is a detail in section showing the abutment and the guide-blockfor the piston. 5 is a detail, being an elevation of the inner face of apart of the wall of the steamchest, showing the groove for the abutment.Fig. (3

is a detail showing a continuous box for the piston-shaft instead of aninnerand outer box. Fig. 7 is a perspective view of the abutment. Fig. 8is a detail in section showing the abutment and its adjusting devices;Figs. 9, 10,11

0 and 12, outline views showing the relative positions of the piston,the inston-shaft, and the walls of the steam-chest at diiterentpoints inthe circle described by the pistonshai't. Fig. 13 is a perspective View,in a diagram form,

5 showing the abutment and piston.

This invention relates to engines in which a piston is employed having atravel in straight lines across the steam-chest and a rolling motionagainst the walls of the steam-chest, pro

40 ducing a compound reciprocating and gyrating motion,bywhichthe end ofthepiston-shaft is caused to describe a circle aroundalinesl1aft withwhich the piston-shaft iseonnected,thcreby driving such line-shaft; andthe objects of the invention are to give the piston an unbroken travelin its circuit around the walls of the steam-chest, thereby preserving aconstant contact between the faces of the piston and the walls of thesteam-chest; to improve the connection between the piston-shaft and theshaft to be driven and havethetwo shaftsin proper alignment and thepiston-shaft properly supported and guided; to furnish a support for thepiston from the flange thereof by which a straight line travel of thepiston across the steam-chest will be insured, and to improve generallythe construction and operation of the engine as a whole; and the natureof the invention consists of the several parts and combinations of partshereinafter described, and pointed out in the claims as new.

In the drawings, A represents the end of the case, which may be formedof a single piece or of two halves, each having a flange, by which andsuitable bolts the two halves are connected together. The outer end ofthe case Alias a flange a, and the inner end has a flange a.

B is a cone-shaped circular chamber in the end A, which chamber at itsouter end terminates in a straight wall I).

G is an annular chamber at the inner end of the case A, which chamberhas a straight wall, and, as shown, the wall of the case A has a passageor opening 0, closed by a cap 0', by which opening communication is hadwith the chamber C.

D is an end plate for closing the outer end of the case A, for whichpurpose the plate is secured to the flange a, by bolts a and, as shown,at one side of the plate D is a foot d, for the passage of the bolts (1'for attaching the plate to the base or support of the engine.

E are annular plates, one for each side of the steam-chest, and one ofthese plates E is 8 attached to the flange a of the case A'by bolts of,so as to make a steam-tight connection between the plate E and the caseA, and the other plate E has an extension or wallE,

.forming an annular chamber 0', similar to the chamber C, and the end ofthis chamber is closed by a plate D, attached to aflange on the end ofthe wall E by bolts (1. This plate D is solid; but the plate D has acentral boss or hub D, in which is a central hole for the reception of asleeve, as shown in Fig. 1.

F is a ring located between the plates E and secured in position betweenthe plates by bolts f, and, as shown, in order to form a firm unionbetween the ring and the plates, each plate on its inner face has ashonlderf,

and the inner face of the ring F is formed on the arc of a circle, so asto form a face or wall f. The ring F can be a continuous one or can bemade of two half-rings, each half-ring having a flange F, shown in Fig.2, by means'of which and bolts f" the half-rin gs are joined together.

G is the steam-chest, formed between the inner facef of the ring F andthe inner faces g of the plates E, and each face g of each plate Eprojects inward, as shown in Fig. 1, so that the steam-chest is wider atits periphery than at its inner edge, and the side walls of thesteam-chest are of a convex shape.

H is an annular flange, the periphery of which fits and coincides withthe face f of the ring F, and, as shown, in the periphery of the flangeH are triangular-shaped packin g-rin gs 71/, one on each side of thecenter of the flange, and each packing-ring is projected and heldoutward bya spring h, located in a recess at one side of the recesswhich receives the packing-ring 7t. The flange H has on each side aninclined face 72, the inclination of which coincides with theinclination of the Walls g, forming on each side of the flange II aconcave face coinciding with the convex face of the side walls g of thesteam-chest, as shown in Fig. 1.

I is the abutmentpassing through the flange H, for which purpose theflange H has a slot or openin 7 and this abutment cuts across thesteam-chest from one side wall to the other and forms a partitionseparating the inlet and outlet ports forthe steam, which ports arelocated on opposite sides of the abutment, as shown in Fig. 4:. Eachside wall or face g of the steam-chest has a groove ,9, (shown in Fig.5,) which groove is cut diagonally across the face or wall, and thesegrooves 9 receive the side edges t" of the abutment- I, by which theabutment is located at one side of the center of the flange in adiagonal plane parallel with a radial line passing through the center ofthe flange, which plane in its passage cuts the radial lines on theflange, except the one with which it'is parallel, as shown in Fig. 2,and this abutment is inclined in its relation to the line of contact ofthe flange with the walls of the steam-chest for the line of contact topass from the exhaust to the supply side of the abutment with anunbroken support in passing from the inner to the outer end of theabutment, and vice versa.

J is a ball made in two parts, one of which has a screw-threaded neck orend j, which enters a screw-threaded hole j in the other POL tion of theball, as shown in Fig.1, and this ball as a wholehas a central annularrecess j, which receives the inner edge of the flange H, for whichpurpose the flange has a central hole for the passage of the end j, sothat the end can be passed through such hole and the female portion ofthe ball be screwed to place, firmly connecting the flange H with theball J, as shown in Fig. 1, and when connected the flange 1-1 and theball J constitute the piston.

The inner end of the abutment I fits against the face of the ball J, forwhich purpose this end has a circular concave face i, conforming to theface of the ball, and, as shown, this inner end of the abutment is of aless width for the purpose of permitting the abutment to cut through thepacking-rings for the ball without destroying the rings. The edges 1" ofthe abutment I fit snugly in the grooves g formed therefor in the innerface of each plate E, and the outer end i of the abutment fits snugly ina groove formed therefor in the inner face of the ring F, so that whenthe abutment is in place it will be steam-tight and prevent the steamfrom passing from the supply to the exhaust Without passing around thesteamchest.

K are the packing-rings for theball J, which rings are located onopposite sides of the ball, and each ring has a bearing-face 7c of aconcave shape to receive the ball, and, as shown, the packing-ring onone side has an opening or hole for the passage of the piston-shaft.

L is a follower located in the chamber 0 of the end case A, and havingits inner endl screw-threaded to enter a screw threaded opening in theplate E, and at, the inner end is a rim or flange Z, which bears againstthe end face of the packing-ring, and a similar follower L is located inthe chamber 0 upon the opposite side of the ball J, and bymcans of thesefollowers the packing-rings K can be advanced as required for wear andfor the purpose of advancing the followers. Each follower has a seriesof holes 722, which come in linewith the opening a, so that by the useof a lever or other suitable tool each follower can be advanced asrequired.

M is a cone-shaped hole or opening through the follower L.

N is the piston-shaft, one end of which is firmly secured to the ball Jat the center thereof, and this piston -shaft extends out from the ballJ and enters the chamber 13 of the case A, as shown in Fig. 1, and ismade to stand at an angle for the side faces h of the flange H to lie incontact with the side faces 9 of the steam-chest G and hold the flangeat an angle to the center of the steam-chest, to preserve a line ofcontact between the flange and the steam-chest.

O is a cone-shaped head lying in the chamber B and the opening M, andhaving on one side a groove 0 to receive boxes a, in which thepiston-shaft N is supported, and these boxes n can be an inner and outerbox, as shown in Fig. 1, or a continuous box, asshown in Fig. 6.

P is a shaft to be driven, entering at its inner end the head 0 at thecenter of the head and secured to the head by a 'key 19, and this shaftP and the piston-shaft N are to be in the same plane one with the other,for which purpose the groove 0 and the hole for the shaft P are in lineone with the other.

Q is a sleeve, through which the shaft P passes, and this sleeve at itsinner end enters IIO the head 0 for the head to revolve thereon, and issecured in the hub or center D by a set-screw g, by means of which thesleeve Q is locked against turning.

R is a channel across the facefof the ring F, which channel runsin astraightline across the steam-chest, as shown in Fig. 4.

S is a sliding block located in the channel R and fitting snugly in thechannel, so as to be free to move back and forth across the steam-chest.This block has a hole 3, which receives the end of a pin '7', firmlysecured in the periphery of the flange H.

T is a plate attached tothe side of the steam chest on the ring F andplates E by bolts t.

U is an opening in the plate T to receive a pipe for supplying steam tothe steam-chest G, which opening U communicates with a supply-port u inthe ring F, leading into the steam-chest on one side of the abutment I.V is an opening in the plate T to receive a pipe for the exhaust of thesteam, for which purpose the opening V communicates with an exhaust port1:, leading from the steamchest G on the opposite side of the abutmentI. The channel or groove It, as shown, is located in line with theexhaust-port u and is wider than the exhaust-port, so as to form abottom for the block S, and, as shown, leading from the exhaust-port oneach side of the channel It is a hole \V to insure a proper exhaust incase the exhaust-port. is not of a suflicient size for exhaustingpurposes.

IV is a base or support 011 which the engine as a whole is mounted, andto which the engine is secured by the foot (I, the bolts (1, the feet 6,and the bolts 6, as shown in Fig. 1.

The abutment I is held for its end t' to be in contact with the face ofthe ball by adjusting-screws z, passing through holes in the plate T andentering screw-threaded holes in the ring F, and, as shown, between theends of the screws and the edge i of the abutment are coiled springs .2,which give a yielding pressure for the abutmentI on the ballJ.

The parts are assembled by entering the packing-ring K into its plate Eand attaching such plate to the end of the case A by the flange a andthe bolts (0. The follower L is inserted in the chamber C and screwedinto the plate E for its end .7 to abut against the packingriug It. Theball J, with the flange II secured thereto, is placed in position forthe ball to enter the packing-ring E. The ring F is attached to theplate E by the bolts f to surround the flange H. The abutment I isslipped into place, passing through the slot 2 and entering at its edgei into the groove g for its end i to lie against the ball and its end iin the groove therefor in the ring F. The plate E, with the wall E,having the packing-ring K therein, is attached to the ring F by thebolts f for the packing-ring to re ceive the ball J and the groove g toreceive the edge t" of the abutment I. The follower I] is inserted inthe chamber 0 and screwed into the plate E for its end Z to abut againstthe packing-ring K. The plate D is attached to the end flange of thewall E by the bolts cl" closing that end of the engine. 0 is enteredinto the chamber B and connected with the shaft N by the groove 0 andthe box or boxes 11. The shaft P is secured in the head 0 by the key 1).The sleeve Q is slipped onto the shaft P and into the end of the head 0,and the plate D is attached to the end of the case A by the flange a andthe bolts a with the sleeve Q in the hub or eenter D, where it is lockedand held by the setserew q, and this sleeve Q can be used to force thehead 0 forward to set the shaft N at the proper inclination, and theplate T is attached in position by the bolts 2, and when the severalparts are together the engine as a whole is attached to the base orsupport \V by the feet (Z c and the bolts (1 e.

The packing-rings K are made to fit the ball .I by advanein thefollowers L and L, and when the engine is in position a steam-supplypipe is attached to the plate T at the opening U, and a steam-exhaustpipe is at tached to the plate T at the opening V, so that steam issupplied through the opening U and the port it to the chamber G on eachside of the flange II, and steam is exhausted from the chamber G 011each side of the flange II through the exhaust-port r and the opening V,and the steam supplied through the supply-port a will pass entirelyaround the chamber G to the exhaust-port 1', and such passage will becontinuous.

In use the steam entering the supply-port 2/ and passing around in thechamber G to escape at the exhaust-port r will carry the flange II backand forth across the steamchamber G by the steam acting first on oneside of the flange H and then on the opposite side as such flangechanges its position in relation to the supply-port. This moving of theflange H to and fro across the chamber G causes the faces 71 of theflange to roll against the walls g of the steam-chamber 011 both sides,and this rolling movement is had by the turning of the ball J in itssocket, formed by the packing-rings K, and from this rolling movementthe end of the piston-shaft N'is made to describe a circle, imparting arotary movement to the head 0, which movement is transmitted to theshaft P, driving such shaft.

The flange II and the ball J form a piston, from the movement of whichthe shaft N is made to describe a circle, and the position of the pistonin relation to the abutment and the movement of the piston-shaft in thecircle d escrib'ed by its end are shown by the diagrams Figs. 0, 10, 11,and 12. The diagram Fig. 9 shows the flange in relation to the abutmentand the position of the piston-shaft N when the flange has moved onehalfof the distance across the abutment in the direction of the arrow, or tothe right, and in this position the contact-line of the flange with thewalls of The head the steam-chest is one-quarter of the distance around,and steam is supplied to the chamber G through the port to on both sidesof the flange H, and steam is exhausted from both sides of the flange Hthrough the ports when the parts are as shown in Fig. 9. The continuedmovement of the flange H in the direction of its travel to the rightcarries the flange over the abutment to the right-hand side, as shown inFig. 10, in which position the contact-line between the flange and thewalls of the steam-chest has been advanced another quarter and the shaftN has been carried to the position shown in Fig. ll,

J which is a half-revolution,and with the parts in the relation of Fig.11 the periphery of the flange on the right-hand edge has passed boththe inlet-port u and the exhaust-port ti and closed both of such portsat the right-hand side of the abutment. At this point the flange Hbegins its return movement across the steanrchest over the abutment I inthe direction of the arrow in Fig. 11, and when the contact-line betweenthe flange H and the walls g of the steam-chest G has been advancedanother quarter the flange H has traveled across the steam-chest to theposition shown in Fig. 11 and the shaft N has been carried around to theposition of Fig. 11 and has describedathree-quarter revolution, and withthe parts in this position steam is supplied through the port a to bothsides of the flange H and steam is exhausted from both sides of theflange I'l through the port '0. The advance of the contact-line betweenthe flange and the walls of the steam-chest for another quarter carriesthe parts into the position shown in Fig. 12, in which the flange hastraveled back across the steam-chest and over the abutment I to closethe supply-port a and the exhaust-port v on the left-hand side of theabutment, and in this position the flange H has made an entire traverseacross the steam-chest and is ready to be carried back in the directionof travel shown in Fig. 9, and with this direction of travel thecontact-line between the flange H and the walls of the steam-chest Gwhen carried around another quarter will bring the parts into theposition shown in Fig. 9, and these movements of the flange back andforth across the steam-chest will continue as long as steam is suppliedto the chamber G. The position shown in Fig. 9 may be regarded as havingthe contact-line between the flange H and the, steam-chest G advancedonequarter around from the starting point, which is the abutment, and inthis position the end of the shaft N has described a quarter-circle, andwith the parts asshown in Fig. 10 the con tact-line between the flangeand the walls of the steam-chest has advanced one-half the distancearound and the shaft N has de scribed half a circle, and with the partsas shown in Fig. 11 the contact-line between the flange and the walls ofthe steam-chest has .advanced three-quarters of the distance around andthe shaft N has described threequarters of a circle, and with the partsas shown in Fig. 12 the contact-line between the flange and the walls ofthe steam-chest has completed its travel around and the shaft hasdescribed a complete circle when the abutment is used as astarting-point.

It will be seen from the foregoing description and the diagramillustrations that, except at two points-namely, the limit of the travelof the flange H in both directions across the steam-chest G-steam isadmitted on both sides of the flange at the supply-port at all times andtravels around from the supply side of the abutment in the space betweenthe flange H, the side walls of the steamchest, and the abutment on bothsides of the flange to the exhaust-port, the result being a constantsupply of steam, which travels continuously, moving the flange H to andfro across the steam-chest through the pressure of the steam in thechest against the abutment on the supply side and against the walls ofthe steam-chest and the faces of the flange, and it will be seen that inthe initial the flange is carried across the steam-chest until half acircle has been described, when the steam space between the flange andthe wall of the steam-chest gradually narrows for the remaining travelof the flange.

The piston formed by the flange H and the ball J is supported in thesteam-chest G for the flange to have a contact-line with the walls ofthe steam-chest by the piston-shaft N and the head 0, andthesteam-chestis divided by the abutment I, so as to have a supply andexhaust side.

The angle of the piston-shaft N is changed for the proper contactbetween the flange H and the walls 9 of the steam-chest by adjusting thehead 0 through the sleeve Q or in any other suitable manner, and theball J is held in position by the packing-rings K, which form a socketfor the ball, by which the ball IIO is supported, and in case of wearthe packing-rings can be advanced to take up the wear by turning thefollowers L and L through the holes m and a suitable lever insertedthrough the opening 0 into a hole m in line with such hole, and afterthe follower has been advanced the tool can be removed and the hole 0closed by the cap or cover 0', and this advance of the packing-rings Kthrough the followers L will be uniform and equal at all points byreason of the engagement of the rim Z with the packing-ring its entirecircle.

The flange H should move over the abut ment without contact, and thisend is secured by means of the channel R and the block S, which travelsback and forth in the channel by reason of its attachment to the flangeH through the pin 7', and as the channel R is in a straight line acrossthe steam-chest G and the block, S moves in this channel it follows thatthe flange H must also move in a straight line across the steam-chest,which line is likew1se the line of the abutment I, and as the space oropening 1/ in the flange II is a trifle wider than the thickness of theabutment I the edges of the flange at the opening 5 will not come incontact with the abutment I, as the flange cannot varyin its courseacross the steam-chest. The connection of the shaft N with the head 0,as shown inl ig. 1, is by an inner-and outer boxnand the groove 0, and,as shown in Fig. (i, this connection is had by the use of a continuousbox at and the groove 1), and in place of using these boxes /1 the shaftN can be connected with the head 0 by a hole formed in the head toreceive the end of the shaft; but in any event the groove 0 and the holein the head 0, which receives the ends of the shaft I, must be in thesame plane one with the other, with the hole for the shaft P at thecenter of rotation of the head 0, which center is the center of the ballJ. The attachment of the shaft N to the head O by the boxes it enablesany slight variation in the alignment to be readily taken up by settingthe box it accordingly, and for this reason the boxes n afford the bestmeans for attaching the piston-shaft N to secure proper alignment.

The wear on the edge or periphery of the flange H is compensated for bythe packingrings 71", which are held against the wall f of the chamber Gby the action of the springs /t,preventing the passage of steam from oneside to the other of the flange ll, except by passing around from thesupply to the exhaust side of the abutment and what little steam passesthrough the opening 1'. Such steam will in no way affect the operationof the piston, as the pressure of the steam on both sides of the flangell is always in a direction to move the flange in the same direction,and by holding the flange ll clear of the abutment at the opening i wearonthe abutment from the travel of the flange ll is prevented, andconsequently wear on the flange to increase the size of the opening i.

The word diagonal in connection with an abutment is a defining word,indicating the position of the abutment in relation to the flange andsteam-chest as tangcntialwith its outer or starting point in line, ornearly so, with the periphery of the ball, and its inner or terminalpoint in or near a vertical line from the center of the ball for theline of the abutment to be outside of the piston shaft, as clearly shownin Fig. 2, and the line of tangentity is one at an angle of forty-fivedegrees, or approximately so, to a horizontal base or other line. Thisdiagonal abutment is in no sense a straight-line radial abutment nor aninclined-line radial abutment, in both of which constructions theradiation is in a direct line from the piston-shaft, and with suchdirect-line radiation the abutment is subjected to a blow from thepiston at each revolution because of the drop of the piston, and theresult of the continuous blows is a wearing out of the abutment at thecenter, allowing an increased back swing for the pis ton, and such backswing produces a backlash on the piston-shaft, causing an uneven motionand not a true circle traverse of-the shaft, and the travel of thepiston over the abutment is a broken interrupted one by reason of thedrop off and the wearing of the abutment out at the center and producesmore or less jar and concussion. onal abutment obviates all thesedefects of a radial abutment, as it gives a continuous unbroken support,over which the piston constantly travels without any drop, thuspreventing back swing of the piston and backlash of the shaft and givingthe shaft a true circle of rotation.

\Vhat I claim as new, and desire to secure by Letters Patent, is

1. The combination, in an engine, of an annular steam-chest, a piston inthe steamchest formed of a flange and a ball, with the flange at thecenter of the ball and traversing the steam-chest on straight lines androlling against the walls of the steam-chest, an abutment cutting theflange diagonally at one side of the center of the piston, and apiston-shaft projecting at one side of the piston from thecenter of theball transversely tothe fla1'1ge,substantially as and for thepurposesspecified.

2. The combination, in an engine, of a steam-chest, a piston inthesteanrchest formed of a flange and a ball, with the flange at the centerof the ball and traversing the steanr chest 011 straight lines androlling against the walls of the steam-chest, an abutment cutting theflange diagonally at one side of the center of the piston, apiston-shaft projecting at one side from the center of the balltransversely to the flange, and a head receiving and supporting thepiston-shaft in an inclined position, substantially as and for thepurposes specified.

The combination, in an engine, of a steam-chest, a piston formed of aflange and a ball, with the flange at the center of the ball andtraversing the steam-chest on straight lines and rolling against thewalls of the steanrchest, an abutment cutting the flange diagonally atone side of the center of the piston, a piston-shaft projecting at oneside from the center of the ball transversely of the flange, a headreceiving and supporting the piston-shaft, and a center bearing for theball, substantially as and for the purposes specified.

:L The combination, in an engine, of a stean1-chest,a piston in thesteam-chest formed The diagsupporting the piston-shaft, a center bearingfor the ball, and a connection between the pistoirflange and thesteam-chest, substantially as and for the purposes specified.

5. The combination, in an engine, of a steam-chest,apistoninthesteam-chestformed of a flange and a ball, with the flange at the centerof the ball and traversing the steamcheston straight lines and rollingagainst the walls of the steam-chest, an abutment cutting the flangediagonally at one side of the center of the piston, a piston-shaftprojecting at one side from the center of the ball transversely to theflange, a center bearing for the ball, a connection between the flangeand the face of the steam-chest, and a driven shaft connected to thehead, substantially as and for the purposes specified.

(3. The combination, in an engine, of a steam-chesthaving convexcontact-walls, a piston in the steam-chest formed of a flange havingconcave side faces and aball, with the flange at the center of the balland traversing the steam-chest on straight lines and rolling against thewalls of the steam-chest, an abutment cutting the flange diagonally atone side of the center of the piston, and a piston-shaft projecting atone side from the center of the ball transversely of the flange,substantially as and for the purpose specified.

7. The combination, in an engine, of a steam-chest having convexcontactwvalls, a piston in the steam-chest formed of a flange havingconcave side faces and a center ball traversing the steam-chest onstraight lines and rolling against the walls of the steamchest, anabutment cutting the flange diagonally at one side of the center of thepiston, a piston-shaft projecting at one side from the center of theball, and a head receiving and supporting the piston-shaft,substantially as specified.

8. The combination, in an engine, of a steam-chest having convexcontact-walls, a piston in the steam-chest formed of a flange havingconcave side faces and a center ball and traversing the steam-chest onstraight lines and rolling against the walls of the steam-chest, anabutment cutting the flange 1 diagonally'at one side of the center ofthepis-v ton, a piston-shaft projecting at one side from the center ofthe ball, a head receiving and supporting the piston-shatt, and a centerhear.- ing for the ball, substantially as and for the purposesspecified.

9. The combination, in an engine, of a steam-chest having convexcontact-walls, a piston in the steam-chest formed of a flange havingconcave side faces and a center ball and traversing the steam-chest onstraight lines and rolling against the walls of the steam-chest, anabutment cutting the flange diagonally at one side of the center of thepiston, a piston-shaft projecting at one side from the center of theball, a head receiving and supporting the piston-shaft, a center bearingfor the ball, and a connection between the flange and the face of thesteanrchest, sub stantially as and for the purposes specified.

10. The combination, in an engine, of a steam-chest having convexcontact-Walls, a piston in the steam-chest formed of a flange havingconcave side faces and a center ball and traversing the steam-chest onstraight lines and rolling against the walls of the steam-chest, anabutment cutting the flange diagonally at one side of the center of thepiston, a piston-shaft projecting at one side from the center of theball, a head receiving and supporting the piston-shaft, a center bearingfor the ball, a connection between the flange and the face of thesteam-chest, and a driven shaft connected to the head, substantially andfor the purposes specified.

11. The combination, in an engine, of a piston formed of a flange and acenter ball, a piston-shaft projecting at one side from the center ofthe ball, and a head receiving and supporting the projected part of thepistonshaft at both the outer and inner ends and holding the pistoninclined, substantially as and for the purposes specified.

12. The combination, in an engine, of a piston formed of a flange and acenter ball, a piston-shaft projecting at one side from the center ofthe ball, a head receiving and supporting the projected part of theshaft at both the outer and inner ends, and a shaft secured to the headand driven thereby, substantially as and for the purpose specified.

13. The combination, in an engine, of a piston formed of a flange and acenter ball, a piston-shaft projecting at one side from the center ofthe ball, a head receiving and supporting theshaft, and a connectionbetween the piston-flange and steam-chest, substantially as and for thepurposes specified.

14. The combination, in an engine, of a piston formed of a flange and acenter ball, a piston-shaft projecting at one side from the ball at thecenter, a head receiving and sup,- porting the pistoirshaft, a drivenshaft connected to the head, and a connection between the flange ofthepiston and the wall of the steam-chest, substantially as and for thepurposes specified.

1'5; The combination, 'in an engine, of a piston formed of a flange anda center ball, a piston-shaft projecting at one side from the center ofthe ball, and a cone-shaped head receiving and supporting thepiston-shaft at both the outer and inner ends in an inclined relation,substantially as and for the purposes specified.

16. The combination, in an engine, of a piston formed of a flange and acenter ball, a

piston-shaft projecting at one side from the center of the ball, acone-shaped head receiving and supporting the piston-shaft at both theouter and inner ends, and a driven shaft connected with the head,substantially as and for the purposes specified.

17. The combination, in an engine, of a piston formed of a flange and acenter ball, a

piston-shaft projecting at one side from the center of the-ball, acone-shaped head receiv- '1 ng and supporting the shaft, and a connection between the piston-flange and the wall of the steam-chest.substantially and for the purposes specified.

18. The combination, in an engine, of a piston formed of a flange and acenter ball, a piston-shaft projecting at one side from the center ofthe ball, and a cone-shaped head receiving and supporting thepiston-shaft, a driven shaft, and a connection between the flange andface of the steam-chest, substantially as and for the purposesspecified.

19. The combination, in an engine, of a piston-shaft and a headreceiving and supporting the projected part of the piston-shaft at boththe outer and inner ends for maintaining the shaft atan inclination,substantially as and for the purpose specified.

20. The combination, in an engine, of a piston-shaft, a head receivingand supporting the projected part of the piston-shaft at both the outerand inner ends, and a connection between the piston and the wall of asteamchest,substantially as and for the purpose specified.

21. The combination, in an engine, of a piston-shaft, a head receivingand supporting the projected part of the piston-shaft at both its outerand inner ends, a driven shaft at tached to the head, and a connectionbetween the piston and the Wall of the steam-chest, substantially as andfor the purpose specified.

22. The combination, in an engine, of a pistonshaft and a cone-shapedhead receiving and supporting the shaft atboth its outer and inner endsafifl attached to a shaftto be driven, substantially as and for thepurpose specified.

23. The combination, in an engine, of a piston-shaft, a cone-shaped headreceiving and supporting the piston-shaft at both the outer and innerends and attached to a shaft to be driven, and a connection between thepiston and the face of the steam-chest, substantially as and for thepurpose specified.

24. The combination, in an engine, of a flange and a ball forming apiston, a pistonshaft projecting at one side from the center of theball, an abutment cutting the flange diagonally, and a cone-shaped headreceiving and supporting the piston-shaft and attached to a shaft to bedriven, substantially as and for the purposes specified.

25. The combination, in an engine, of a flange and ball forming apiston, a pistonshaft projecting at one side from the center of theball, an abutment cutting the flange, and a head receiving andsupporting the piston-shaft at both the outer and inner ends andattached to a shaftto be driven, substantially as and for the purposesspecified.

2G. The combination, in an engine, of a flange and ball forming apiston, a pistonshaft projecting at one side fromthe center of the ball,an abutment cutting the flange,

'a head receiving and supporting the pistonshaft and attached to a shaftto be driven, and a connection between the flange and the face of asteam-chest, substantially as and for the purpose specified.

27. The combination, in an engine, of a flange and ball forming a pistonand a connection between the flange and face of a steam-chest forholding the piston in straightline travel, substantially as specified.

28. The combination, in an engine, of a steam-chest having contact-wallswith a diagonal groove and an abutment held by the diagonal grooves anddividing the steamchest, substantially as and for the purposesspecified.

29. The combination, in an .engine, of a piston formed of a flange and acenter ball, an abutment cutting through the flange and engaging theface of the ball, and devices for moving the abutment to preserve thecontact with the ball, substantially as and for the purposes specified.

30. The combination, in an engine,- of a piston formed of a flange and acenter ball, an abutment cutting through the flange and bearing againstthe face of the ball, and adjusting-screws for advancing the abutment tocompensate for wear against the ball, substantially as and for thepurposes specified.

251. The combination, in an engine, of a piston formed of a flange and acenter ball, an abutment. cutting through the flange and bearing againstthe face of the ball, setscrews for advancing the abutment, andtension-springs for holding the abutment in contact-with the ball,substantially as and for the purposes specified.

The combination, in an engine, of the piston-shaft N, projecting at oneside of the piston, and the head 0, receiving and supporting theprojected part of the piston-shaft at both the outerand inner ends,substantially as and for the purposes specified.

The combination, in an engine, of the piston-shaft N, projecting at oneside of the piston, the head 0, receiving and supporting the projectedpart of the piston-shaft N at both its outer and inner ends, and thedriven shaft. P, connected with the head 0, for holding the shaft N atan inclination, substantially as and for the purpose specified.

234:. The combination, in an engine, of the flange II and ball J,forming a piston, the piston-shaft N, projecting at one side of thepiston, the head 0, receiving and supporting the shaft N, and thesliding block S, connecting the flange with the wall of the steam-chest,substantiallyas and for the purpose specified.

35. The combination, in an engine, of the steam-chest G, the flangell,and ball J, forming a piston, the piston-shaft N, projecting at one sideof the piston, the head 0, receiving and supporting the shaft N, thechannel R, and the sliding block S, connected with the flange II,substantially as and for the purposes specified.

36. The combination, in an engine, of the steam-chest G, flange II, andball J, forming a piston, the piston-shaft N, projecting at one side ofthe piston, head 0, receiving and supporting the shaft N, driven shaftP, channel R, and sliding block S, substantially as and for the purposespecified.

37. The combination, in an engine, of the steam-chest G, having Walls g,flange II, havmg faces h, and ball J, forming a piston, the piston-shaftN, projecting at one side of the ball J, head 0, receiving andsupporting the piston-shaft, the shaft P, and the channel R, and slidingblock S,forming a connection between the flange II and thestea1n-cl1est,substantially as and for the purpose specified.

38. The combination, in an engine, of the steam-chest G, having convexside walls g,

the flange H, having concave side faces h, and the ball J, forming apiston, the abutment I, cutting the flange diagonally at one side of thecenter, and thepiston-shaft N, projecting at one side from the center ofthe ball J and supported by the head 0, substantially as and for thepurpose specified.

39. The combination, in an engine, of the steam-chest G, the pistonformed of the flange H and the center ball J, the packing-rings K,receiving the center ball J, and the screwthreaded followers L and L,forming a firm backing for and simultaneously and uniformly advancingthe packing-rings to take up wear, substantially as specified.

40. The combination, in an engine, of the steam-chest G, the pistonformed of a flange H and a center ball J, the packing-rings K, receivingthe center ball J, the piston-shaft N, projecting at one side from thecenter of the ball J, and the head O,receiving and supporting the shaftN at both its outer and inner ends,substantially as and for the purposespecified.

41. The combination, in an engine, of a steam-chest G, the piston formedof the flange H and a center ball J, the abutment I, the packing-ringsK, receiving the center ball J, the piston-shaft N, projecting at oneside from the center of the ball J, and the head 0, receiving andsupporting the shaft N at both its outer and inner ends, substantiallyas and for the purposes specified.

42. The combination, in an engine, of a steam-chest G, the piston formedof the flange H and a center ball J, the abutment I, the packin g-rin gsK, the screw-threaded followers L L, engaging the full face of andforming a firm backing for the pack ing-rings, the pistonshaft N,projecting at one side from the center of the ball J, the head 0,receiving and supporting the piston-shaft, the shaft P, and the channelR, and block S, substantially as and for the purpose specified.

43. The combination, in an engine, of a steam-chest, havingcontact-walls, a piston in the steam-chest formed of a flange and acenter ball, and an abutment dividing the steanrchest and cutting theflange of the piston on a diagonal line for giving the piston anuninterrupted traverse, substantially as and for the purposes specified.

LEVI M. SHAV. \Vitnesses:

0. WV. BOND, J. R. ANDREWS.

